Not a good idea, it'll create more piston rock. Under the pin bosses are a better spot to remove material. The old 12-1/2:1 440 domed pistons were like cinder blocks weight-wise and I've taken a huge amount of weight out of a bunch of those in those areas. Lighter wrist pins are also an option. Just know that in a street engine, you will never know the difference if the pistons are 10 pounds each or 2 pounds each. In a race engine you will.
I was looking at the pistons and the top of the pistons seem to have a good bit of material, as well as the pin bosses. Not sure if I'll actually sit down and get after it but I did buy a small milling machine a few years back so this might be a worth while project; if only to learn. I have twelve .030 over NOS pistons that I've separated into 1st choice and 2nd choice. I'm thinking I might give it a go on the 2nd choice set.
